To the scores of New York office workers descending into the subway on an unusually humid September Friday, it was just another dark-windowed limousine pulling up outside the Liberty Street headquarters of the New York Federal Reserve Bank.

But the car, the chauffeur, its passenger and the purpose of the journey were not run of the mill. Few of the commuters, worried for their jobs in the midst of the worst financial crisis since the Great Depression, could have guessed at the excesses behind the dark glass.

Sitting in the back was John Thain, the Clark Kent-lookalike chief executive of Merrill Lynch. The gaunt-faced Mr Thain, 53, had been summoned, along with 30 of the world’s most powerful bankers, by Henry Paulson, the then US Treasury Secretary and Tim Geithner, the man who would succeed him, to devise a bailout for Lehman Brothers, the Wall Street bank teetering on the brink of collapse.

So many limousines pulled up outside the New York Fed on September 12 that they created a jam in the narrow streets of downtown Manhattan. While the men who controlled the world’s banking system idled in the congestion, all with the desire to avoid having to bail out Lehman, Mr Thain stood out from the others.

He was the highest paid of them all. Having been poached by Merrill Lynch the year before from the New York Stock Exchange, he took a salary, bonus and benefits worth $83 million in 2007. As befitted the best-paid man on Wall Street, he also had the best-paid chauffeur, who took home an annual $230,000.

For the man, nicknamed “I Robot” because of his mechanical coldness, it was also fitting that he should have just left one of the most lavishly furnished offices in Manhattan. As soon as he was appointed to Merrill Lynch and installed in the World Financial Centre bank headquarters, he used $1.2 million of company funds to make his office feel more like home.

Or more like one of his five homes – an apartment on Park Avenue, a ten-acre estate adjoining Westchester Country Club and properties in Rye and Harrison, New York as well as one in Vail, Colorado. His new office fittings included an $87,784 rug, the same amount for two chairs and, for all those crossings out and downward profit revisions, a $1,405 waste paper basket.

Once at the New York Fed meeting – which lasted late into the night and continued into Saturday – Mr Thain realised that Mr Paulson was making little progress in finding a consensus about how to save Lehman. By Saturday night, with no bailout on the table and no firm bidder, Mr Thain concluded that not only would Lehman collapse but that Merrill would be next, and he phoned Ken Lewis, the chief executive of America’s biggest retail bank, Bank of America, based in Charlotte, North Carolina.

By Sunday afternoon the deal to sell Merrill Lynch for $50 billion to BoA was signed and sealed. It was not just the takeover Mr Thain raced through. He also tried to seize a $10 million bonus for himself and forced through the early payment of up to $4 billion of bonuses to Merrill’s top executives despite knowing about the rapidly escalating losses the bank was incurring.

By December, just three months into the merger, Mr Lewis began to discover from his own integration team that Merrill was on course to lose $3 billion in the fourth quarter and $15.4 billion over the year. The shock forced him this month to go to the US Treasury and beg for $118 billion in asset guarantees and $20 billion in rescue financing.

On Thursday, Mr Lewis flew from Charlotte to Manhattan to sack John Thain. As every financier knows, consistency is key to success. How appropriate, then, that a banker who had long enjoyed the excesses of Wall Street should choose to go skiing in the rich resorts of Colorado once BoA’s losses were out in the open.

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